From: Sasha Neftin <sasha.neftin@intel.com> stable inclusion from stable-v5.10.113 commit 46b0e4f998ceead45f273be4d282b7fbb70f6125 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5ISAH Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 907862e9aef75bf89e2b265efcc58870be06081e ] An infinite loop may occur if we fail to acquire the HW semaphore, which is needed for resource release. This will typically happen if the hardware is surprise-removed. At this stage there is nothing to do, except log an error and quit. Fixes: c0071c7aa5fe ("igc: Add HW initialization code") Suggested-by: Dima Ruinskiy <dima.ruinskiy@intel.com> Signed-off-by: Sasha Neftin <sasha.neftin@intel.com> Tested-by: Naama Meir <naamax.meir@linux.intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Acked-by: Xie XiuQi <xiexiuqi@huawei.com> --- drivers/net/ethernet/intel/igc/igc_i225.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/igc/igc_i225.c b/drivers/net/ethernet/intel/igc/igc_i225.c index 553d6bc78e6b..624236a4202e 100644 --- a/drivers/net/ethernet/intel/igc/igc_i225.c +++ b/drivers/net/ethernet/intel/igc/igc_i225.c @@ -156,8 +156,15 @@ void igc_release_swfw_sync_i225(struct igc_hw *hw, u16 mask) { u32 swfw_sync; - while (igc_get_hw_semaphore_i225(hw)) - ; /* Empty */ + /* Releasing the resource requires first getting the HW semaphore. + * If we fail to get the semaphore, there is nothing we can do, + * except log an error and quit. We are not allowed to hang here + * indefinitely, as it may cause denial of service or system crash. + */ + if (igc_get_hw_semaphore_i225(hw)) { + hw_dbg("Failed to release SW_FW_SYNC.\n"); + return; + } swfw_sync = rd32(IGC_SW_FW_SYNC); swfw_sync &= ~mask; -- 2.20.1